Genetic background and GxE interactions modulate the penetrance of a naturally occurring wing mutation in Drosophila melanogaster

Many genes involved in producing complex traits are incompletely penetrant. One such example is vesiculated, an X-linked gene in Drosophila melanogaster that results in wing defects. To examine the genetic architecture of a complex trait (wings containing vesicles), we placed a naturally occurring variant into multiple autosomal backgrounds and quantified penetrance and expressivity at a range of developmental temperatures. We found significant epistasis, genotype-by-environment interactions, and maternal effects. Sex and temperature effects were modulated by genetic background. The severity of wing phenotypes also varied across different genetic backgrounds and expressivity was positively correlated with penetrance. We also found evidence of naturally segregating suppressors of vesiculated. These suppressors were present on both the 2nd and 3rd chromosomes, and complex interactions were observed. Taken together, these findings indicate that multiple genetic and environmental factors mo...参与调控复杂性状形成的诸多基因，其外显率往往并非完全。其中一个典型案例便是囊泡化（vesiculated）基因：该基因是黑腹果蝇（Drosophila melanogaster）中的X连锁（X-linked）基因，突变后会引发翅膀缺陷。为解析“翅膀携带囊泡”这一复杂性状的遗传结构，我们将一个自然存在的变异等位基因导入多个不同的常染色体遗传背景中，并在一系列发育温度梯度下，对该性状的外显率（penetrance）与表现度（expressivity）进行了定量检测。研究结果显示，该性状存在显著的上位性（epistasis）、基因型-环境互作（genotype-by-environment interactions）以及母体效应（maternal effects）；性别与温度效应同样受到遗传背景的调控。翅膀表型的严重程度随遗传背景不同而存在显著差异，且表现度与外显率呈显著正相关。此外，我们还发现了自然分离的囊泡化基因抑制因子的相关证据：这类抑制因子分别位于第2号和第3号染色体上，且彼此间存在复杂的互作关系。综合来看，本研究结果表明，多种遗传与环境因素共同作用于……